diff --git a/src/classes/PStartupHandler.cpp b/src/classes/PStartupHandler.cpp
index a70edfb1..26462d6f 100644
--- a/src/classes/PStartupHandler.cpp
+++ b/src/classes/PStartupHandler.cpp
@@ -29,6 +29,7 @@
  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  ***************************************************************************/
 
+#include <cstdlib>
 #include <iostream>
 #include <fstream>
 using namespace std;